i am trying to deploy my contract to testnet using the following :

Web3 = require('web3')

solc = require('solc')

web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));

code = fs.readFileSync('testVote.sol').toString()

contract = solc.compile(code)

abi = contract.contracts['Voting'].interface

code = contract.contracts['Voting'].bytecode

TestContract = web3.eth.contract(abi)

deployedContract = TestContract .new({data: code, from: web3.eth.accounts[0], gas: 4700000})

contractInstance = TestContract .at(deployedContract.address)

but the address is always undefined, why is it not getting mined? I am using geth

  • Did you unlock your account before sending the transaction? – jeff Jan 28 '17 at 21:55
  • TestContract.new is async - are you sure you waited for the system to actually create the contract before invoking deployedContract.address? – Chris Hafey Jan 29 '17 at 1:14

You need to wait the transaction to be mined before you can know the address of your contract.

Here is a sample deployment script for Node 7 (read full tutorial):

// Copyright 2017 https://tokenmarket.net - MIT licensed
// Run with Node 7.x as:
// node --harmony-async-await  deploy.js

let fs = require("fs");
let Web3 = require('web3'); // https://www.npmjs.com/package/web3

// Create a web3 connection to a running geth node over JSON-RPC running at
// http://localhost:8545
// For geth VPS server + SSH tunneling see
// https://gist.github.com/miohtama/ce612b35415e74268ff243af645048f4
let web3 = new Web3();
web3.setProvider(new web3.providers.HttpProvider('http://localhost:8545'));

// Read the compiled contract code
// Compile with
// solc SampleContract.sol --combined-json abi,asm,ast,bin,bin-runtime,clone-bin,devdoc,interface,opcodes,srcmap,srcmap-runtime,userdoc > contracts.json
let source = fs.readFileSync("contracts.json");
let contracts = JSON.parse(source)["contracts"];

// ABI description as JSON structure
let abi = JSON.parse(contracts.SampleContract.abi);

// Smart contract EVM bytecode as hex
let code = contracts.SampleContract.bin;

// Create Contract proxy class
let SampleContract = web3.eth.contract(abi);

// Unlock the coinbase account to make transactions out of it
console.log("Unlocking coinbase account");
var password = "";
try {
  web3.personal.unlockAccount(web3.eth.coinbase, password);
} catch(e) {

console.log("Deploying the contract");
let contract = SampleContract.new({from: web3.eth.coinbase, gas: 1000000, data: code});

// Transaction has entered to geth memory pool
console.log("Your contract is being deployed in transaction at http://testnet.etherscan.io/tx/" + contract.transactionHash);

// http://stackoverflow.com/questions/951021/what-is-the-javascript-version-of-sleep
function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));

// We need to wait until any miner has included the transaction
// in a block to get the address of the contract
async function waitBlock() {
  while (true) {
    let receipt = web3.eth.getTransactionReceipt(contract.transactionHash);
    if (receipt && receipt.contractAddress) {
      console.log("Your contract has been deployed at http://testnet.etherscan.io/address/" + receipt.contractAddress);
      console.log("Note that it might take 30 - 90 sceonds for the block to propagate befor it's visible in etherscan.io");
    console.log("Waiting a mined block to include your contract... currently in block " + web3.eth.blockNumber);
    await sleep(4000);


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.